This year’s Nobel Prizes honor two sets of scientists whose innovative work revolutionized how peptic ulcers are treated and the way many pharmaceuticals and plastics are made.

The 2005 Nobel Prize in Physiology or Medicine was awarded to a pair of Australian researchers whose work proved the bacterium Helicobacter pylori, not stress and lifestyle, is the chief cause of peptic ulcers. The 2005 Nobel Prize in Chemistry went to a trio of chemists who developed a technique for manufacturing pharmaceuticals, plastics, and other products that produces less waste.